ive got a lamp with a meter in the base, just like you are building. in fact i think it has the same meter in it. i remember seeing a knob inside the meter that said S<-->F that looks like slow/fast to me. im guessing it's for calibration or something. have you tried playing with that? if it does in fact adjust the speed, i would think it would only be a small adjustment. my meter lamp spins pretty slow too, and i have a 150 watt bulb in it (big room)
